Pilish is an extraordinary form of constrained writing that straddles the boundary between language and mathematics. Pilish literature is written in such a way that the number of letters in each successive word is equal to the successive decimal places of pi, 3.14159265359…
The first few numbers of pi can be memorized using the mnemonic “How I wish I could calculate pi,” while extra decimal places can be added by memorizing ever longer sentences (“How I want a drink, alcoholic of course, after the heavy lectures involving quantum mechanics” takes pi to its 14th decimal place).
However, as a form of constrained writing, Pilish was taken to an extreme by the American mathematician Mike Keith in his 1996 short story Cadaeic Cadenza, which comprises 3835 words all following the decimal sequence of pi (0s are words 10 letters long).
As if that weren’t mindboggling enough, in 2010 Keith published the novella Not A Wake which pushed that total to 10,000. Check it out here.